import os
import unittest

test_classes = [cls[:-3] for cls in os.listdir('.') if cls.startswith('test_') and cls.endswith('.py')]

suite = unittest.TestSuite()
sub_suites = []
for tcls in test_classes:
    tc = __import__(tcls)
    sub_suites.extend([getattr(tc, s) for s in tc.__dict__.keys() if s.startswith('suite')])
suite.addTests(sub_suites)

if __name__ == "__main__":
    runner = unittest.TextTestRunner()
    runner.run(suite)
